Gas dispensing system



Nov. 16, 1948. w, C, BUTTNER ErAL 2,453,968

NW 36 1948- w. c. BUTTNER Erm. v 2,453,9

' GAS DIsPENsING SYSTEM Filed Jan. 9, 1942 5 Sheets-Sheet 2 PatentedNov. 16, 1948 GAS DISPENSING SYSTEM William C. Buttner, Winnetka, and Harold L. Norway, Evanston, Ill., assignors to The Bastian Blessing Co., Chicago', Ill., a corporation of Illinois Application January 9, 1942, Serial No. 426,206

16 Claims. (Cl. 62-1l The present invention relates to a device for dispensing liquefied petroleum products partially or completely saturated with other organic substances in the form of gas or-vapor mixture for use in household appliances and lhas lfor one of its objects the provisionof a construction which can be used as original equipment or as conversion equipment to so convert existing liquefied petroleum gas dispensing systems in order that the heavier hydrocarbons, such as pentane, hexane and octane ranging-from light gasoline to kerosene and heavier or other organic hydrocarbon products which have little, if any. vapor pressure at normal temperatures can be used and dispensed safely as a substitute for natural gas or commercial butane gas.

Dispensing devices have heretofore been provided which utilize air under pressure and means for entrainlng the vapor oi liquefied gas for purposes of combustion. Due to the presence of oxygendn the air used these dispensing devices,

. particularly if they are faulty or kept in poor repair, may cause hazardous conditions to exist by generating an explosive mixture and precipitation under cold conditions. Also. the use of electric power is required to compress air for most of these devices.

One oi' the objects of the invention is to provide s. gas dispensing device in which no oxygen is present or employed in; utilizing the hydrocarbons or organic substances as a concentrated source of heat conveyed in its vapor form by a vapor carrier.

Furthermore, it has been the experience with conventional air gasoline or air pentane systems that not'only is the explosion hazard present. but the air-itself dilutes the calorinc content oi the gas dispensed and thereby requires specially designed burners and large service lines to make the system acceptable for household installations.

A further object of the invention is to provide a new and improved construction in which a vapor mixture comparable to commercial butano provision of a device of the class described wherein the gas generated is of uniform caloriilc value, whether the storage container is full or almost empty, yet will still have a burnable gas ii through carelessness the storage tank has been allowed'to become empty.

. A further object of the invention ls to provide new and improved parts for convertingthe present commercial butane systems for use with vapor.

mixtures, including the vapor of octane or hexane as original equipment or as conversion equipment. A further object of the invention is to provide a device of the class described which is easy tomanufacture and service, inexpensive to build and maintain and requiring no electric motor equipment and which complies with -the safety standards prescribed foriiqueiled petroleumga's dispensing systems.

These being among the objects of the present invention, other and further objects will become apparent from the drawings and the description relating thereto and the appended claims.

Referring now to the drawings- Fig. l is a vertical section taken through a storage tank as buried, preferably, below the frost line, and illustrates one oi the embodiments of the invention as it appears when placed in service.

Figs. 2 and 3 are fragmentary views similar to Fig. 1 showing the construction of certain modilcations of the device illustrated in Fig. l'. which modiications may be employed' to convert conventional gas dispensing tanks to use other fuels.

Fig. 4 is a vertical section through a vertical slip tube gauge which can be employed to convert conventional constructions of the objects expressed herein without need for other than a lim` ited opening from the tank to the outside atmosphere.

Storage tanks used with bulk systems that are buried underground are rated with regard to the fuel that can safely be stored in them. In view of the size of the storage tank required for bulk systems it has been the practice to design the tank for use with commercial butane, which fuel makes it possible to make the tank a great deal lighter than one required for propane, thus effecting a substantial saving in metal The vapor pressure oi commercial butane at expected underground temperatures seldom, if

ever, reaches pounds per square inch gauge.

whereas` with propane under like temperatures the vapor pressure could runas'much as one hundred and fifty pounds per square inch gauge or more possibly during lling operations. Consequently, in the bulk systems for -commercial butane the rated safe pressure of buried storage vides a maximum pickup tanks is approximately one hundred pounds per square inch gauge. At this rating, tanks being manufactured for underground systems at the present time and those already in the ground for dispensing comercial butane would not pass inspection if propane were to be stored in them.

A further comparison of propane and commercial butane as a fuel reveals that propane has less caloriilc value. per cubic foot of vapor than commercial butane, xand. if used in commercial butane appliances would tend to cause the llame to float away from the burner when the burners are full on. The calorific content of commercial' butane vapor is approximately 3000 B. t. u.s per cubic foot at 62 F. and 14.7 pounds per square inch pressure absolute as compared with propane having approximately 2500 B. t. u.s per cubic foot.

Consequently. in many ways in for commercial butane in systems designed for butane dispensing. l

In the present invention, by way of illustrating the use of hydrocarbons or organic substances, hexane or octane which have substantially no diiiiculty would be experienced using propane as a substitutev pane therein in its vapor pressure gauge at the temperatures experienced in the ground below the frost line, is stored in the tank rated for commercial butane and propane in its vapor phase is brought at a reduced pressure into intimate contact with a preferably constant body of stored liquid to absorb sufilcient of the vapor of the liquid to provide a resulting gas of approximately the same' B. t. u. content as that experienced with commercial butane.

In order to safeguard and prevent overpressuring the system with high propane pressures, the

propane vapor is regulated to a reduced pressure,v

.preferably before entering the conilnes of the tank as at low a pressure as approximately pounds per square inch guage, this pressure being found to be a desirable pressure that proof approximately 20% or hexaneY by weight which has a caloric value of approximately 4800 B. t. u. per cubic foot or 15% of octane by weight which has a calorihc content of approximately4 6200 B. t. u. per cubic foot.

l The resulting mixture of propane vapor and the vapor of ether hexane or octane is stored below the frost line and used as desired, being conducted into the dwelling at the pressure determined by thepropane regulator and reduced as gas inside of the dwelling to-service pressure of approximately 11 inches water column by a second regulator. after which the gas may be heated, if desired, and metered for use in an appliance. A two stage pressure reduction can be provided or used for the gas mixture.

A Referring now to Fig. 1, a storage tank I0 is buried below the frost line Il in the ground I! where it will be subjected to a substantially constant temperature above 32 F. Hexane or octane Il is introduced into the tank through a filler connection il in a fitting Il that is mounted upon the upper end of a riser pipe II welded to the tank Il as at I1.

Other valves and controls such as a. vapor return connection Il, pressure and liquid level gauges 2l and 2| are present in the fitting with' excess flow and back pressure check valves (not shown) used within as more particularly shown in the co-pe'nding application of William C. Buttner. and Baven L. Sundstrom, Serial No. 397,096, now Patent No. 2,405,998, granted August 4 20. 1946, reference to which is hereby made. A conduit 22is mounted on the fitting Il and extends down intothe tank to the bottom where flexible ,hose pieces 2l, preferably made of paraprene extend laterally along the bottom of the tank. The hose pieces II are perforated throughout their lengths to provide" bubble ports 2 4, and these ports aresupplied preferably with propane in its vapor phase through the conduit 22 from a pipe 25 which extends preferably underground to the delivery side of a pressure reducer Il mounted upon the outlet connection 21 of a portable'propane cylinder 20 having a supply of proliquidand vapor phases. The propane cylinder 2l is disposed upon a concrete block 3l in a cabinet si at theside of the foundation i2 of a house I3. A hand valve Il. having an automatic filler valve therein, if desired, is detachablyvmounted upon the propane cylinder in the propane supply line to control the supply of propane furnished thereto for use in the system.

After the tank I0 has been charged with a supply of hexane or octane the hand valve Il is turned on and propane plied to the hose pieces 2l at the pressure predetermined by the regulator, which pressure is preferably 5 pounds per square inch gauge., but being capable of being varied in relationship to the desired calorific value of the gas supplied for use. The propane vapor will bubble up from the ports 24 through the hexane or octane and entrain a certain amount of hexane or octane until the pressure in the tank reaches the pressure determined by the regulator 2l.

The vapor mixture thus generated and stored in the tank l0 is then educted from the tank through a hand valve Il into a service line 3l buried below the frost line. through the founda-` tion 32 into the cellar 3l of the dwelling A3l as controlled by a hand valve 31 located in the cellar. From the hand valve 21 the vapor mixture is conducted to a pressure reducerlh which reduces the pressure to Il inches of water column and thereafter the vapor mixture is conveyed through a heat exchanger 4I, if desired, and

meter 42 to an appliance in the house, such as 4 It has already been. mentioned that the pro-l pane vapor will entrain the hexane or octane and since the caloriilc value of hexane and octane is much higher than commercial butane, a` 15 to 20% entrainment by weightof the octane or hexane by propane respectively, develops a vapor mixture having a B.. t. u. content that compares very favorably with the B. t. u. content of the commercial butane'with which the system and the appliances were originally designed, namely. approximately 3000 B. t. u. per cubic foot, as measured at 62 F. and 14.7 pounds per square inch absolute.

Referring pow to Fig. 2, a device is shown which can be used as original or conversion equipment to utilize a storage tank intendedfor dispensing butane for the purposes mentioned. The

in its vapor phase sup-v tank 80 is provided vvwith a .riser pipe 8i welded thereto as at and threaded as at 83 ,to receive a fitting 56 illustrated diagrammatlcally/ The --propane vline 26 is disposed within a protecting housing 55 having a cover 8,6. The propane supply line 2t in.v conversion linstallati/ons can be run along the ground below the ground level for protection and `into the-housing through an opening l81 to terminate vas vv'at 88 in a downwardly extending nipple 8,0 which carries a nut Y l 6 The construction shown in Fig. 2 is particularly adapted for conversion equipment since no part of the fitting need be changed except the removal 8| makingfup tov a femalethread upon the ller connectiont of the itting 66, said filler con -nection having a back pressure check valve 83 the top ofthe riser pipe Bi at a threaded opening et. l

In combination with the fitting 54 is provided a container s1 adapted to slip downwardly through the riser pipe 8| as carried by a sup` porting pipe 8d threaded at its upper end in the eductlon opening 68.

The container 61 is 'adapted to receive liquid therein from the bottom of the tank 58 and propane in its vapor phase from the top of the tank for intimate mingling within the container 81. In accomplishing this, the container is providedwith a liquid eductlonl conduit `1t which leads from the bottom of the tank, as at 1|, to a valve 12 controlled by a float' 13, the oat 13 moving the valve to closed position when a predetermined level 1d. of liquid is reached in the container 81. Below the valve 12 the container is packed with felt or rockwool 1d which becomes saturated with the liquid in the container 61. Propane is introduced into the container at the bottom thereof in its vapor phase through a conduit 1B mounted at 11 at the top of the container B1. The use of felt or rock wool breaks up the bubbles into small bodies ofgas which are forced under pressure differentials to increase the surface `oi' contact of the gas as much as possible.

Above the level 14 of the liquid i8 in the container t1 is provided ya space in which mixed vapors similar to those present in the container I@ are stored. and in this particular embodiment the service pressure regulator dil is mounted preferably upon the riser pipe within the housing 55 in communication with the service passageway tt.

of the butane liquid eductlon conduit, if it is present. and the replacement thereof by threading the attachment shown into the threaded eductlon opening 86. The container 81 is rigidly supported i l by a lock nut 18 disposed to one side of the center of the container so that the'container after it is lowered in place can be moved laterally of the riser pipe 8| topermit a slip tube liquid level gauge, such as that shown at llin' Fig. 1. to be lowered from the' fitting without hlndrancevfrom the container 61. y

l Comparing Fig. 2 with the embodiment illustrated in Fig. A3, Fig. 2 is designed to store the mixed vapors inside of the container 61, whereas in Fig. 3 the device is so constructed and arranged having 'certain features regarding simplicity Ll (l with the device shown in Fig. 2 the commingling of propane and liquid hexane or octane, or both, is a constant factor since the' level 14 is constant in the container and the felt 15 comprises a diffuser of constant characteristics, with liquid continually supplied that has not been depleted of its light ends before reaching the interior of the container 81.

Then when the vapor mixture used in the appliance d3 is drawn to the service conduit 38a the pressure in the container is reduced sunlciently to draw propane vapor through the passageway 1B up through the felt 15 and liquid it inside of the container 61 to entrain the liquid contentfor purposes of combustion. Whenever the liquid 'Id falls below a. predetermined level the float 13 opens the valve 12 and any pressure diilerences existing between the inside of the container 81 and the tank 50 will force liquid from whereby the vapor mixture is stored in the storage tank 58.

In the embodiment shown in Fig. 3, the container 81a is filled with felt 15 and propane vapor is supplied to the top of the container''la through a conduit 68a threaded into an opening a in the fitting 54a which communicates with the propane cylinder 28 through a passage 8| having a back pressure check valve 82 therein within the threaded opening 83 which receives the propane supply conduit 25. The usual eductlon passageway of a batch system is indicated at 84a with the hand shutfoff valve 65 and regulator 40 in the service line, the same as those described in connection with Fig. 2.'

Propane vapor entering through the conduit 88a passes through the felt 15 which is soaked with the liquid I3 that enters the container 61a through the openings 84 provided in the bottom ofthe container, but in view of the fact that the vapor mixture is withdrawn from the main tank 50 rather than from the container 61a, the pressure differential of the embodiment shown in Fig. 3 is 'the opposite to that existing in Fig. 2. Withdrawal of vapor from the tank 50 reduces the pressure therein suiliciently forthe vapor pres- Y sure entering the container 81a. to` force its way down through the felt 15 in intimate contact with the liquid supported thereby and bubbles out through the holes 84 laden with-the liquid with whichit has been in contact.

Referring to Fig. 4, the construction and operation thereof is. somewhat similar to that shown in Fig. 3, otherwise with certain modifications theconstruction Ashown in Fig. 4 being similar to the slip tube gauge disclosed and described in the copending application of William C. Buttner and Harold L. Norway, Serial No. 403,512, reference to which is hereby made.

The slip tube gauge |00 is an improved one and is designed to serve several functions that |02 as sealed. bypacking |03 compressed by a flanged nut |04. The lower end of the body |02 is machined as at |05 to provide a valve seat and is externally threaded as at |08 with a tapered thread whereby the slip tube; gauge can be re- :,esaoes ceived and removed fromv the top of a iitting similar to the htting Il describedin Fig. 1.

. The lwer end or me tub-.usr member m is threaded as at |01 at the bottom and |03 at the top. A container |I is provided with an opening I in the top thereof and is received over the tubular member IIII and held slidably in place by an internally threaded head I|2 received upon' the threads |01. On top of the container I I0 a washer i I3 is mounted which cooperates with the seat |04 when the slip tube gauge is raised to full height so packing |03 can is required.'

as to provide a seal by which the be serviced if at any time'servicing Threaded into the bottom of the head II3 is a retainer nut |I4 holding a resilient disk III in place. The container ||0 has openings |I0 inthe side thereof just below the disk lil when the head IIZ is in its uppermost position in the container lio, thereby providing communication between the passage ||1 in the'tubular member |0I ular run oi tanks, the spring |34 serving to urge the container |I0 upwardly and slidably upon the head I2 to establish a seal between the resilient disk H5 and the hanged wall |23 when the slip tube is lowered all the way into the tank. The upper end of the flanged nut |04 is provided with one of the cooperating elements of the bayonet Joint |30 and the head |3| that is shown threaded to the upper end of the slip tube member |0| is provided as at |32 with the other element of the bayonet element. In this way, the upward creeping of the slip tube |0| under tank pressure is prevented when the bayonet joint is established.

The head I3| has a threaded chamber |33 therein separated from the tube .i 0| by a partition |34.- A hole |35v is drilled through the partition concentricaliy4 with respect to the threads in the wall of the chamber and-a valve or vent Plug as- 8 by these markings the liquid level and the contents ef the tank can be determined. The vent plug is then tightened, and, if there is no further use for the tube. the tube is lowered again and locked in place by the bayonet Joint.

A protecting cap |4| is threaded to the body |02 as at |42, to provide a sealed compartment |43 therein by engaging in sealed relationship a gasket |44 mounted in a recess |40 machined in the shoulder |43 at the bottom of the threading |42. At its top. the cap I4| is provided with a fitting |41 threaded ais at |43 and chamfered al at to receive the male member of a connector comprising preferably a pigtall (not shown) having an excess iiow cheek valve therein that is connected to the propane tank 23. In this way. propane vapor at aregulated pressure is supplied to the compartment |43.

The head I3| is elongated and provided with s'umcient stock to have machined therein a threaded opening IBI' which receives a cage member |52, carrying a back pressure check valve |03 therein that cooperates with the seat |04.

In this way,whenever pressure present in the compartment |43 of the cap |4| exceeds the press ure inside of the storage tank vapor will flow from the compartment |43 through the valve |03 and the passage ||1 into the tank through the circuitous passageway |2 i and openings |22. as indicated by the arrows Ill.

Although it is not necessary to do so. it is found desirable to till the containn' below the retaining nut ||4 with felt 1l for the same purposes and with the same results as that described in connection with the embodiment illustrated in Fig. 3.

sembly |33 carrying a pin |31 surrounded by a s washer |33 is received into the threaded chamber |33. The pin |'31 is so constructed and arranged that it extends through and beyond the hole |35 at all operative positions so that it serves to provide an annular flow area for fluid through the hole |35 which is very dimcult to obstruct by loose particles as compared with aconventionalopenldrill hole.

A laterally extending passageway |40 leads from the chamber |33 near the bottom thereof so that gas or liquid may be discharged therefrom when the slip tube gauge is operated to determine the level of the liquid in the tank.

In testing for the liquid level in the tank with j the slip tube gauge. the tube is raised to its upper limit. thV vent plug |30 is loosened until Jthe leakage of escaped gas informs the operator that the gauge is in operation, the container |I0 having dropped to provide open communication between the passage I1 and the openings IIB. The tube is then pusheddown slowly until liquid discharges from the vent hole |40, at which time a reading is taken from calibratedv marks (not shown) on the outer surface of the-tube I 0I. and

Although certain improved embodiments of the present invention ,have been shown and described herein and ways have also been suggested by which the present invention may be utilized= in various dispensing systems, it will be apparent to those skilled in the art that various and further uses, modifications and changes may be made without departing from the spirit or substance of the invention set forth in the objects and description, the scope of which is commensurate I with the appended claims.

'1 What is claimed is:

1. In combination. a container buried below the frost line for storing a fuel having a vapor pressure less than the vapor pressure of butane, a second container supported inside the first, porous means in the second container forV dividing the container/into minute passageways, means for supplying to one of the containers the vapor of a fuel having a vapor pressure in excess of butane, and means'for withdrawing a mixture of said vapor and the rst fuel from the other of said containers.y

2. 'In combination. a container buried below the frost line for storing a fuel having a vapor pressure less than the vapor pressure of butane, a fitting connected to the container, a second container supported inside the first upon the fitting, means in the second container for dividing the container into minute passageways, means for supplying to one of the containers the vapor of a fuel having a vapor pressure in excess of butane, and means for withdrawing a mixture of said vapor and the first fuel from the other of said containers.

3. In combination, a container buried below the frost line for storing a fuel having a vapor pressure less than the vapor pressure of butane, said eontainerhaving an opening through a wall thereof, afitting oonnnected to the container in c ` tainer through the opening, a second container insertable through the opening and supported inside the first upon the fitting, porous means inthe second container soaked with liquid of the fuel in the nrst container, means for supplying lto one of the containers the-vapor of a fuel having a vapor pressure in excess of butane to pass through said porous means, and means for withdrawing a mixture of said vapor and the ilrst fuel from the other of said containers.

4. In combination with a tank for storing fuel in its liquid phase, a device slidably mounted with respect to the tank for determining the level of liquid in the tank comprising, a conduit, a valve for controlling the outow of fuel from the tank through the conduit, a back pressure check valve means permitting the inflow of vapor to the tank through the conduit, and means for receiving said vapor and bringing said vapor and liquid fuel into intimate contact in the tank.

5. In combination with a tank-for storing fuel in its liquid phase, a gauge device slidably mounted with respect to the tank for determining the level of liquid in the tank comprising, a conduit,

a valve for controlling the outflow of fuel through the conduit from the tank, a back pressure check valve permitting the inow of vapor to the tank through the conduit. and means for receiving said vapor and bringing said vapor and liquid fuel into intimate contact including an element comprising a porous material soaked with the liquid in the tank.

in its liquid phase, a device slidably mounted with unication with the interior of the conv l a buried storage tank for ,storing fuel in its liquid and vapor phases and a fitting mounted with respect thereto, the combination of s storage tank above-ground containng .a supply oi' liquefied petroleum gas therein, a conduit leading from thetop of the above-ground tank to the belowgroundtankincluding a passageway through the fitting for conveying gas in its vapor phase from the above-ground tank to the below-ground tank, a pressure regulator in said conduit,'an eduction conduit including a passageway through the'flttingfor removing vapor from the below-ground tank,y and means interposed between said passageways for `bringing the liquid fuel and said gas in its vapor phase into intimate contact with one another including a porous material.

10. In combination with a tank for storing fuel in its liquid phase, a device mounted upon'the tank -for determining the level of the liquid in the tank and comprising a conduit element, a bleed passageway connecting the conduit -element with atmosphere for the outflow of uelfrom the tank through the conduit, a back pressure check valve means permitting the inflow of vapor to the tank through the conduit, a removable cover means for enclosing the chock valve means for sealing the bleed passageway from atmosphere including an element for connectingv ,it to a source of supply of liqueiled petroleumgas in its vapor form, for bringing said vapor land liquid fuel into ,intimate contact in the tank.

respect to the tank for determining the level of liquid in the tank and for introducing a vapor fuel comprising, a conduit, a valve for controlling the outow of fuel through the conduit from the tank, a back pressure check valve means permitting the inflow of vapor to the tank, and means for bringing said vapor and liquid fuel present in the tank into intimate contact, including an element comprising a porous material slidably mounted upon the conduit to expose alternatively the conduit to the interior of the tank directlyv and the interior of the tank through said material.

7. In a ilqueed petroleum gas'dispensing system, the combination. of a storage tank buried below the ground, a container in said tank, means for educting liquid from the tank to the container including a oat valve responsive to the amount of fuel in the container, a conduit bypassing the oat valve for supplying vapor from' the tank to the bottom of the container, means 11. In a llqueiied petroleum gas dispensing system having a pressure storage tank. a unitary gtl ting connected to the tank and having an outlet connected to a service conduit ,leading rto a pressure regulator, means for tting liqueed petroleum gas to the tank includingaback pressure for supplying vapor under pressure to the tank,

rand means for @ducting vapor from the container to conduct same to a place of use.

8. In a liqueed gas dispensing system having a buried storage tank for storing fuel in its liquid form and a fitting mounted with respect thereto, the combination of a storage tank aboveground containing a supply of liquefied petroleum gas therein, a conduit leading from the aboveground tank to the below-ground tank including a passageway through the tting to conductfgas from the above-ground tank to the below-ground tank. a pressure regulator in said conduit, and an eduction conduit including a passageway through the fitting for removing vapor from the belowground tank, and means interposed between said passageways for bringing the liquid fuel and said gas into intimate contact with one another.

9. In a liquefied gas dispensing system having check valve and a connector member, and means upon the connector member for interchangeably connecting thev admitting means with asource of liquefied petroleum gas in its liquidphase and a sourcerof liqueed petroleum fgasin'its vapor phase, and means for bringing said gas in its vapor phase and gas in its liquid phase in the tank into intimate contact'witheach other between said check valve and outlet.

12. In a liquefied petroleum gas dispensing system having a pressure storage tank buried 'below the frost line of the ground, a unitary fitting con- V,nected to the tank and having an outlet connected to a service conduit leading to a pressure regulator, means for admitting liquefied petroleum gas to the tank including a back pressure check valve for opening under the inflow of a gas under pressure, a connector member carried by said means,

means upon the connector member -for interchangeably connecting the admitting means with a source pf liquefied petroleum gas in its liquidl phase and a source of gas in its phase under pressure and means-for bringing said vapor gas in its vapor phase and gas in its liquid-phase in the tank into intimate contact with 'each other @between said check valve and outlet.

13. In a liquefied petroleum gas dispensing system. Ihaving apressure storage tank, a unitary tting connected to the tank and having an outlet connected to a service conduit leading to a pressure regulator, means for admitting liquefied petroleum gas to the tank including a back pressure check valve, a source of liquefied petroleum gas under pressure in yits vapor phase, means for reducing the pressure of the vapor gas, means for interchangeably connecting the admitting means with a source of liquefied petroleum gas in its and means arranged to receive vapor andV 'low the ground,

Aassumes I l1 liquid phase and said gasat a reduced pressure, and means for brlngingsaid vapor gas in its vapor phase and gas in its liquid phase in the tank into intimate contact with each other between said check valve and outlet.

14. In a liquefied petroleum gas dispensing system. the combination of a storage tank buried bea container supported invsald tank, means for 'eductingliquid from the tank to the container includinl a oat valve responsive to the amount of fuel in the, container, a conduit bar-passing the noat valve and extending from a point near the top ofthe tank and having an opening within the container-and near the bottom thereof. means for supplying vapor to the tank'at a predetermined pressure for passage through said conduit. and means for educting vapor from the container.

` l5. In a liquefied petroleum gas dispensing system, the combination of a storage tank buried below the ground, a ntting connected to the tank. a container in said tank supported with respect tov the fitting, means for educting liquid from the tank to the container including a valve responsive the top of the tank the container, a conduit the bottom ofthe y 16. In combination with a for storing fuel in its liquid phase. a device mounted with respect to the tank for gauging the level of liquid in the tank including a conduit, a valve for controllinl the outnow of fuel from the tank through the conduit during gauging operations. check valve means opening in the' direction of flow admitting fuel vapor to the tank through the conduit, means for introducing gas in its vapor phase throuah said valve into said conduit, and means for receiving said vapor fuel and bringing said'vapor fuel and liquid fuel into intimate contact in the WILLIAM C. BU'I'I'NER. HAROLD L. NORWAY.

REFERENCES CITED AThe following references are of record in the file of this patent:

n UNITED STATES PATENTS Number OTHER REFERENCES Page 308, Handbook Butane-Propane Gases,

' second edition, published by' Finley and Rahman.

Table, page 45, Handbook Butane-Propane Gases, third edition, published by Western Business Papers, Inc. 

